Height advisor gains FAA STC approval for more than 500 aircraft

OLATHE, Kan. / February 2026 – Garmin (NYSE: GRMN) has announced the availability of the GHA 15 height advisor for certified aircraft, following the award of Supplemental Type Certificate (STC) approval by the Federal Aviation Administration (FAA). The approval permits installation in more than 500 certified Class I and II aircraft.

Previously approved only for experimental aircraft, the GHA 15 is a compact and lightweight height advisor that uses radar technology to provide height above ground level (AGL) information. In certified installations, the system can display height AGL on compatible GI 275 electronic flight instruments.¹

Radar-based height measurement

The GHA 15 determines height AGL by transmitting radio waves to the ground and measuring the time taken for the signals to return. The system processes hundreds of measurements per second and applies advanced digital filtering to maintain continuous readings, including over water or in challenging terrain environments.

AGL readouts are displayed on the GI 275 electronic flight instrument at altitudes up to 500 feet AGL.¹

Audio callouts and cockpit integration

Using data from the GHA 15, the GI 275 can provide configurable AGL audio callouts.² Beginning at 300 feet AGL, the system provides audible callouts at selected intervals down to 1 foot AGL. Pilots can configure the altitudes at which callouts begin and end.

Precise AGL information may assist pilots during landing and when operating in areas with limited barometric altimeter setting information, such as backcountry environments.³

The GHA 15 integrates all electronics into a single module that attaches to the underside of the aircraft. Slightly larger than a deck of cards and weighing less than one pound, the unit requires minimal space and modification for installation.

Availability

The GHA 15 is available now for certified aircraft at a suggested retail price of USD 2,695. Further information is available at Garmin.com/GHA15.

Garmin provides avionics and technology solutions to general aviation, business aviation, rotorcraft, advanced air mobility, government and defence, and commercial air transport customers. The company is the recipient of the Robert J. Collier Trophy for Garmin Autoland, a certified autonomous emergency system designed to control and land an aircraft without human intervention.

¹ Digital readouts display only on GI 275 ADI, HSI, MFD and standby ADI variants. GI 275 ADAHRS-equipped model required.
² Provided through GI 275 audio output; compatible audio panel, intercom or headset required.

³ The GHA 15 provides advisory information only and may not be used for decision altitude or decision height in IFR conditions.